Hydrogen purifiers include a CO remover which reduces carbon monoxide in a hydrogen-containing gas generated through a reforming reaction. The hydrogen-containing gas is generated through the reforming reaction by using a raw material of which the constituent elements are at least carbon and hydrogen. The hydrogen-containing gas is, after passing through the hydrogen purifier, supplied to a fuel cell and used for electric power generation by the fuel cell.
The fuel cell may be any one of various types of fuel cells including a solid polymer fuel cell, a phosphoric-acid fuel cell, and a solid oxide fuel cell. Although in general the CO remover is configured to reduce carbon monoxide through an oxidation reaction, there are also proposed CO removers configured to reduce carbon monoxide through a methanation reaction (see Patent Literature 1 and Patent Literature 2, for example).